Arrangement of electric-furnace electrodes



T. M. HVIDSTEN AND A. H. INGELSRUD.

ARRANGEMENT 0F ELECTRIC FURNACE ELEcTRoDEs.

APPLICATION FILED MAR. I9. |919.

1 ,359,6'7. Patented Nov. 16, 1920.

S Figl. p

Invetors, Thorlef Mandt Hv'ldsten,

\ Ar Hildor e srud.

l Attorneys.

UNITED'STATES PATENT OFFICE.

THORLEIF MANDT HVIDSTEN AND ARNE HILDOR INGELSRUD, 0F CHRISTIANIA,NORWAY, ASSIGNORS TO DET NOBSKE AKTIESELSKAB FOR ELEKTROKEMISK INDUSTRI,OF CHRISTIANIA, NORWAY. I f

ARRANGEMENT OF' ELECTBIC-FURNACE. ELECTRDES.

To all whom z'tma concern.:

Be it known that we, THORLEIF MANDT HvIDs'rEN and ARNE Hinnon INGELSRUD,subjects of N orwa and residents Christiania, in the ingdom of Norway,have invented certain new and useful Imrovements in the Arrangement ofElectricurnace Electrodes, of which the following is a specification.

This invention relates to electric furnace electrodes and has for itsobject an arrangement of such. electrodes which makes possible the useof electric arcs burning above the molten bath of electric furnaces.

Several constructions of elect-ric furnaces employ such electric arcs,but there are always certain difficulties connected with these knowntypes of furnaces. These difficulties are avoided in our presentinvention.

In order to obtain the best results with open electric arcs they must bearranged so as to concentrate their radiation on the molten bath withoutheating too strongly the walls, roof or other parts of the furnace.

According to our present invention great advantages are obtained ascompared to the hitherto known electrode arrangements. 7e can start thefurnace in a very simple man ner without the use of a foreign source ofheat, and our open-electric arc is strongly convex toward the bath ofthe furnace, thus concentrating its Heat of radiation on the bath, Whilethe walls and roof of the furnace are well protected. Further theelectrodes may be regulated in a simple manner during operation of thefurnace.

In the accompanying drawings which form a part of this application,-

Figure 1 represents a vertical sectional View of an electric furnaceembodying this invention, taken on the line II-II of Fig. 2.

Fig. 2 represents a plan view of the furnace.

Fig. 3 represents a fragmentary elevational view of the top of thefurnace as viewed in the direction of the arrow III of Fig. 2, certainparts being omitted for clearness of illustration, and

Fig. 4 represents a side elevation as viewed in the direction of thearrow IV of Fig. 2.

Referring more particularly t0 the draw- Specification of LettersPatent. `Patented Nov' 16, 1920. Application led March 19, 1919. i

Serial No. 283,519.

ings, a represents an electric furnace on which electrode guides Z2 aremounted. These guides are each pivotally mounted as at Z'on mantles u,which are mounted in openlngs in the roof of the furnace. Each of theelectrode guides b is connected by a link c with a collar d which isslidably mounted for Vertical adjustment on a standard e mounted on thetop of t'he furnace. The links are ypivoted at their inner ends to the'collar, and at their outer vends are pivotally connected in any suitablemanner to the electrode guides. Each link is adjustable in length bymeans of a turn-buckle z', and there is thus provided an independentangular adjustment for each electrode guide. bimultaneous adjustment ofthe electrode guides for effecting the angular relation of theelectrodes in the furnace may be had by vertical adjustment of thecollar d. The means for adjusting this collar include a lever f which ispivotally connected at its inner end to the collar, and at its outer endto a nut, mounted on a screw which is controlled by a hand-wheel h. Thelever is fulcrumed at a point g on a suitably supported bracket. Byturning the wheel 71, in one direction, the lever will be actuated so asto lift the collar d, and thus decrease the angle between theelectrodes, and by a reverse movement of the wheel, the collar will belowered, and thus increase the said angle.

he electrodes 7c are each supported by an electrode holder slidablymounted on one of the electrode guides in such manner as to allowlongitudinal adjustment of the electrode with respect to its guide. Theelectrodes project into the furnace through the mantles u.

These mantles are preferably watercooled, and make a fairly tight jointwith the electrodes, being flared to permit the angular adjustment ofthe electrodes above described.

In addition to the individual and simultaneous adjustment of the angularrelation of the electrodes, means are provided for effecting individualand simultaneous adjustment of the distance which the electrodes projectinto the furnace.

These means include cords p which are attached at their outer ends tothe electrode suitably supported on the furnace and which is rotatableby means of a crank m, and ratchet connections between the shaft and thedrums are provided so that the drums may be simultaneously rotated withthe shaft upon turning the crank m, or individually operated by turningtheir respective hand-wheels o.

The above described mechanism therefore provides means for regulatingthe depth of the electrodes, both individually and colle'c tively withrespect to the charge, their angular relation one to the other, and tothe charge, and the distance apart of their ends, and further providesVmeans whereby the electrode ends may be grouped at various points inthe furnace as desired.

The invention has been illustrated as applied to a furnace which may betilted for discharging its contents, and when so applied it is obviousthat the entire electrode apparatus is tiltable with the furnace withoutnecessary change of any adjustment at which the electrodes may be fixed.

While the furnace is shown as equipped with three electrodes andoperating means therefor, it will be understood that the number ofelectrodes may of course be varied without departing from the invention.

In order to start the furnace, We proceed as folloWs,-

A layer of coke or similar material is placed on the bottom of thefurnace, and the electrodes are adjusted so that their ends contact withthe coke at a suitable angle and distance apart. An' electric current isnow applied and the heating of the furnace will take place without thegreat variation of current present where the starting is effected byforming electric arcs directly between the electrodes.

When the furnace has reached the temperature desired for the-process inquestion we gradually lift the electrodes and at the same time changetheir angle, thusl establishng an open electric arc ata suitabledistance above the bath of the furnace.

We have found it advantageous t'o arrange the electrodes in such manneras to be able to vary their angle With the horizontal plane from about67 to about 30. On account nf electro-dynamic effects the electric arcwill during operation of the furnace be blown toward the bath of thefurnace. The electrodes themselves will therefore protect the roof ofthe furnace against radiation of j heat from the arc.

Both the common and the separate regulating devices of the electrodesmay easily be operated at any time, and the electrodes may always bebrought into the most advantageous position without breaking theelectric current. le also obtain another advantage by our arrangement ofthe electrodes, as the electrodynamic forces effecting the blowing ofthe arc toward the bath of the furnace increase in strength inproportion to the amperage of the current. If the resistance of the arcfor some reason or other is decreased thus causing a stronger current topass between the electrodes, the electrodynamic forces willautomatically blow the arc farther down thus increasing its length andalso its electric resistance. Thus the electric current will tend tostabilize itself by our arrangement of the electrodes.

The foregoing detailed description has been given for clearness ofunderstanding, and no undue limitation should be deduced therefrom, butthe appended claims should be construed as broadly as permissible, inview of the prior art.

Ve claim.

l. The combination in an electric furnace, of a plurality of electrodestherefor, means for effecting a simultaneous adjustment of theelectrodes in respect to their depth in the furnace, and means foreffecting a simultaneous angular adjustment of the electrodes.

2. The combination in an electric furnace, of electrodes therefor, meansfor effecting a simultaneous adjustment of the electrodes and foreffecting individual adjustment thereof in respect to their depth in thefurnace, and means forieffectin a simultaneous angular adjustment' ofthe e ectrodes.

3. The combination in an electric furnace, of electrodes therefor, meansfor effecting adjustment of the electrodes in respect to their depth inthe furnace, and means for effecting a simultaneous and individualangular adjustment of the electrodes.

4. The combination in an electric furnace, of electrodes therefor, meansfor effecting a simultaneous adjustment of the electrodes and foreffecting individual adjustment of the electrodes in respect to theirdepth in the furnace, and mea-ns for effectin a simultaneous andindividual angular a justment of the electrodes.

5. The combination in an electric furnace, of electrodes therefor, andmeans for effecting' a simultaneous and individual angular adjustment ofthe'electrodes.

6. The combination in an electric furnace, of electrodes therefor, andmeans for effecting a simultaneous angular adjustment ofv of electrodestherefor, means for effecting a simultaneous angular adjustment of theelectrodes, and means for effecting adjustment of the distance apart oftheir ends.

8, The combination in an electric furnace, of electrodes therefor, andmeans for effecting a simultaneous and individual angular adjustment ofthe electrodes and for effecting adjustment of the distance apart oftheir ends.

9, The combination in an electric furnace, of electrodes therefor, meansfor effecting a simultaneous and individual angular adjustment of theelectrodes, and means for effecting adjustment of the distance apart oftheir ends.

10. The combination in an electric furnace, of electrode guides mountedfor angular adjustment with respect tothe furnace, electrode holdersmounted for adjustment longitudinally of the guides, means for effectinga simultaneous and individual angular adjustment of the guides, andmeans for effecting a simultaneous and individual longitudinaladjustment of the holders relatively to the guides.

11. The combination in an electric furnace tiltable into a position fordischarging its contents, of a plurality of electrodes for the furnace.and means for effecting adjustment of the electrodes with respect totheir depth in the furnace and with respect to their angular relation toeach other, said means being tiltable with the furnace without necessarychange of any adjustment at which the electrodes may be fixed.

12. Arrangement of electrodes in electric furnaces comprising amechanism for simultaneously moving all electrodes in longitudinaldirection and another mechanism fory simultaneously changing the angleof all electrodes.

13. Arrangement of electrodes in electric furnaces comprising amechanism for simultaneously moving all electrodes in longitudinaldirection and also for adjusting each separately in longitudinaldirection, and further comprising a mechanism for simultaneouslychanging the angle of all electrodes and also for adjusting the angle ofeach electrode separately.

14. Arrangement of electrodes in electr-ic furnaces comprising amechanism for simultaneously moving all electrodes in longitudinaldirection and another mechanism for simultaneously changing the angle ofall electrodes, the angle between each electrode and thehorizontal planebeing variable from 670 to 300, the electrodes thus protecting the wallsand roof of the furnaceagainst radiation of heat from the electric arc.

15. Arrangement of electrodes in electric furnaces comprising amechanism for simultaneously moving all electrodes in longitudinaldirection and also for adjusting each electrode separately inlongitudinal direction, and further comprising a mechanism forsimultaneously changing the angle of all electrodes and also foradjusting the angle of each electrode separately, the angle between eachelectrode and the horizontal plane being variable from 67 to 300, theelectrodes thus protecting the walls and roof of the furnace againstradiation of heat from the electric arc.

16. .Arrangement of electrodes in electric furnaces comprising amechanism for simultaneously moving all electrodes in longitudinaldirection and also for adjusting each electrode separately inlongitudinal direction, and further comprising a mechanism forsimultaneously changing the angle of all electrodes and also foradjusting the angle of each electrode separately, the latter mechanismcomprising a centralvertically sliding body and levers connected witheach electrode and also connected with said sliding body.

17. Arrangement of electrodes in electric furnaces comprising amechanism for simultaneously moving all electrodes in longitudinaldirection and also for adjusting each electrode separately inlongitudinal direction, and further comprising a mechanism forsimultaneously changing the angle of all electrodes and also foradjusting the angle of each electrode separately, the latter mechanismcomprising a central vertically sliding body and levers connected witheach electrode and also connected with said sliding body, each leverbeing provided with a right and lefthand screw for adjustment ofk eachelectrode separately.

Signed at Christiania, Norway, this 13th of January, 1919. THORLEIFMANDT HVIDSTEN. AHNE HILDOR INGELSRUD.

